Question about Supergame

Ecernosoft · July 5, 2022

Hi!

After the problem with Concerto and POKEY, I wanted to use a SUPER cartridge for my game BUT I have some questions. (again...)

1. In terms of ROM layout, do the 16kb banks for Super staert at $4000 and then go up by $4000 bytes each bank (Ex. bank 0 = $4000, Bank 1 = $8000, Bank 2 = $C000, and so on)

2. When using SUPER, do I have access to ROM at $3000-$3FFF?

3. Since I want to use POKEY@4000 (if I can't do it at $450 anymore), will $c000-$FFFF be bank 2? (Ex. Bank 2 = $C000-$FFFF)

Thanks.

+Bruce-Robert Pocock · July 5, 2022

I'm not sure if I understand the question, but perhaps this will help.

1. No, the 16kiB banks each start at $8000, except the last one, which starts at $a000

2. I don't know of any configuration that has ROM at $3000

3. POKEY can be mapped at $0450 or $4000 as you wish, it won't affect ROM banks but will affect extra RAM.

In a banked ROM like Supergame, typically all of the banks will occupy the same space, e.g. $8000 - $bfff. You then will bank switch to select which bank is active, in this case by writing to $8000 (since it's a ROM address, no actual write occurs, but the bank switch happens in stead). So each ROM bank occupies the same range of addresses.

In Supergame, in particular, the last bank is available all of the time at $a000 - $ffff, so that bank is where you'll put the 7800 signature and your NMI/IRQ/RES vectors.

Supergame RAM would be accessible at $4000-$7fff. If you don't want the RAM there, you could map the POKEY there in stead. Someone else will have to provide the details, I do not have one in my Concerto.

So a typical Supergame + RAM would have:

TIA + MARIA @ $00

Zero Page RAM @ $80 - $ff

Stack @ $0100 - $01ff

System RAM @ $1800 - $203f, $2100-$213f, $2200-$27ff (and mirrors)

Cartridge RAM @ $4000 - $7fff

Banked ROM @ $8000 - $bfff

Last ROM bank fixed @ $a000 - $ffff

There is also a newer format called Souper, which I don't know about as well. Perhaps someone can provide that information if that's the one you meant. I don't think that Souper works with Concerto though?